1. Field of the Invention
The present invention relates to blocking for use in roof systems and, more particularly, to an expansion joint curb comprising one or more preformed, uniform component structures fabricated from a non-corrosive, durable material, such as galvanized steel, steel, aluminum or plastic and including a lower anchoring flange for attachment to the roof structure, a central portion including vent means formed therein, and an upper flange defining a mounting surface for attachment to various roof components and equipment thereto.
2. Description of the Related Art
Generally, roof systems used on most building structures, and particularly commercial buildings, require some type of blocking to provide a base for the attachment of roofing components such as, but not limited to, gravel stops, eves, drips, fascia, gutters, vent stacks, roof top equipment, expansion joints, roof curbs, copings and cant strips. Traditionally, wood is used for roof blocking and typically consists of one or more stacked wood boards (e.g., 2 inch by 4 inch or 2 inch by 6 inch boards) which are nailed to the roof structure and each other to provide a built-up base at various locations on the roof system wherein it is necessary to mount the roofing components and equipment. Presently, wood blocking is used on virtually all roof systems which require blocking for the purposes described above.
Despite its widespread use in roof systems, there are significant drawbacks and shortcomings associated with the use of conventional wood blocking. In particular, wood is susceptible to damage and deterioration from moisture, termites, ants, and other natural enemies. Further, because wood is a solid material, it does not provide for venting capabilities to permit escape of moisture and gasses from within the roof. The lack of adequate venting is a contributing factor of premature roof failure. Additionally, wood has limited pull-out characteristics for holding nails and other fasteners, thereby requiring a considerable amount of hardware to attach roofing components. Wood, being a natural product, is also prone to irregularities such as areas of reduced dimension, warping, and splintering. This makes it difficult, if not impossible, to achieve a straight, uniform blocking configuration. Furthermore, the dimensions of wood are limited to lumber industry standards which often does not correspond to the dimensions of roofing components, such as roof insulation or lightweight concrete thickness, expansion joint heights and equipment sizes.
In view of the shortcomings of traditional wood blocking used in roof systems, as set forth above, there exists an urgent need in the construction industry for an alternative blocking structure which overcomes the above-described problems. More specifically, there is a need for a blocking assembly which provides for uniform dimensions in accordance with desired size and configuration specifications and which further provides for venting of the roof system. Additionally, there is a need for a roof blocking system which significantly reduces costs for labor and materials associated with the installation of blocking and the attached roofing components.
The present invention is directed to a blocking assembly for roof systems and replaces traditional wood blocking which is currently used on building structures to facilitate the attachment of various roofing components, materials and equipment including, but not limited to, expansion joints and covers (flat type, curb type, or curb to wall).
The blocking system includes one or more components which are preformed in accordance with desired size and shape specifications. The components, fabricated from galvanized steel, steel, aluminum, plastic or other non-corrosive, durable materials, each including an anchoring flange, an upper flange and intermediate portion. The anchoring flange is structured and disposed for mating attachment to the roof structure underlying an insulation layer or lightweight concrete layer on the roof system. The intermediate portion extends upwardly from the anchoring flange. The upper flange extends from the intermediate portion and defines a mounting base for attachment of an expansion joint cover or other roofing components, materials and/or equipment thereto. Vent means are provided in the intermediate portion to allow escape of moisture and gasses which otherwise remain trapped within the roof system. This helps to reduce the likelihood of premature roof failure, and thereby extends the life of the roof system.
With the foregoing in mind, the present invention has the following objects and advantages over the conventional wood blocking structure presently used in most roof systems.
It is particularly, a primary object of the present invention is to provide a blocking assembly for roof systems comprising one or more pre-formed components manufactured from galvanized steel, steel, aluminum, plastic or other corrosion-resistant materials to replace traditional wood blocking and thereby providing resistance to deterioration from moisture, insects, warping, and the like.
It is a further object of the present invention to provide a blocking assembly comprising one or more components which are formed and/or molded in accordance with desired size and configuration specifications for use at specific locations of a roof system.
It is still a further object of the present invention to provide a blocking assembly having a pullout resistance which is significantly greater than that of wood, thereby requiring less hardware, labor and materials to install the blocking and attached roofing materials.
It is yet a further object of the present invention to provide a blocking assembly which is pre-formed and fabricated to conform to a roof structure.
It is still a further object of the present invention to provide a blocking assembly for roof systems which includes venting means for allowing moisture and gasses to be released from the roof assembly, thereby reducing the likelihood of premature roof failure.
It is still a further object of the present invention to provide a blocking assembly for roof systems and, more particularly, an expansion joint curb for use at an expansion joint of a roof system and including means for attachment of an expansion joint cover thereto.
It is still a further object of the present invention to provide one or more integral components fabricated from a non-corrosive, durable material for forming an expansion joint curb at an expansion joint of a roof system which, once installed, becomes integrated with the roof structure.
It is still a further object of the present invention to provide an expansion joint curb assembly for roof systems which is less expensive than wood materials traditionally used for constructing expansion joint curbs.